Ore-concentrator.



No 769,231. PATENTED SEPT. 6, 1904.

G. E. PERKINS.

ORE OONGENTRATOR.

APPLIGATIOXT FILED JUNE 13, 1908 N0 MODEL.

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UNITED STATES Patented September 6, 1904.

PATENT OFFICE.

ORE-CONCENTRATOR.

SPECIFICATION forming part of Letters Patent No. 769,231, a ed September6, 1904.

Application filed June 13, 1903. Serial No. 161,354. (No model.) I

To all whom itmay cancer/1.;

Be it known that I, GEOR E E. PERKINS, a resident of the city ofProvidence, in the county of Providence and State of Rhode Island,haveinvented certain new and useful Improvements in Ore-Concentrators; and Ido hereby declare that the following-is a full, clear, and exactdescription thereof, reference being had to' the accompanying drawings,and to'the letters of reference marked thereon, which form a part ofthis specification. V

This invention pertains to improvements in ore-concentrators, and hasfor its object to collect and return the partly-separated pulp, or thatportion known as middlings, back to the table, where it is deposited ata point just below the pulp-feed to the table, thereby materiallyincreasing the percentage saved of the richer or more valuable portionof the material during this second separation.

The invention consists of novel features and parts and combinations ofthe same, as will be fully described hereinafter and then pointed out inclaims.

' A practical embodiment of the invention is represented in theaccompanying drawings, forming a part of this specification, in whichsimilar characters of reference indicate corresponding parts in allthe'views- Figure 1 is a plan view of the table, showing my spout ortrough in position to conduct and deposit the middlings around and belowthe pulp-feed. Fig. 2 is a side elevation of the table, showingthe-spout for conducting the middlings from the end of the table back tothe elevator. Fig. 3 shows the mechanism for imparting to the table areciprocating motion. Fig. 4 shows the elevator, the trough leading toit, and the spout leading from it.. Fig. 5. is an enlarged perspectiveview of the main feed or distributing trough, showing the distributing 7holes through the rear wall of the same. Fig. 6 is a detail sectionalview on the line 6 6, Fig. 1.

Referringzto the drawings, A is the table, which tapers from the headtoward the foot,- where it is the narrowest, and is transverselyinclined, causing the gangue or waste pulp to be dischargedat its loweredge and the mineral or richer portion at the foot thereof.

This table is provided with longitudinal riffles 4, attached to itsupper face, which are of unequal, length, increasing from the upper edgeof 'the' table downward, where they are the v longest, the lowermostrifile-extending nearly the full length of the table. To the right oftherifiie extremities ,(see Fig. 1) there is a portion B of the table whichis smooth or free-from rifiies.

H is the main feed-spout, through which the material is'fed to. thedistributing-trough I.

This trough runs along the upper edge of the table, extending nearlythroughout its length. On the lower edge and through the rear wall ofthis trough are a series of holes L. (See Fig. 5.) A dam or stop-wall Jis placed in said trough a short distance from the pulpfeedend,.forminga pocket for holding and distributing the pulp on thetable'througli said holes L. The trough beyond this dam is for thepurpose of receiving water through the supply-pipe K and distributing itover the table through the series of holes L in its section for thispurpose. Atthe narrow end or foot of the table is a receptacle C forreceiving the concentrates or richer portion of the separated material.

E is a spout or trough extending from the foot of the table along theside to the elevator F. The apron G extends along the, side'of the tableand is for the purpose of conducting the gangue or waste over thistrough E, causing it to be deposited into asuitable drain or wastetrough below. Near the foot of the table the space or aperture D is leftopen, through which flow the middlings or that portion of the pulp fromwhich the richer mineral .has not been entirely extracted. Thesemiddlingsare conducted through the aforesaid trough E to the elevator F,byiwhiclf the'yv are,raised.a'nd deposited into trough M', which troughin turn conducts them around back of the distributingtrough I, wherethey aredeposited onto the table beyond the point where the initial pulpis discharged onto the table.

To the head end of the table is attached the mechanism which gives saidtable a longitudinal reciprocating movement and is de-. scribed asfollows: o is a keeper which is engaged by one extremity of-a verticallever 0,

fulcrumed at (Z on a support 6, mounted on the stationary frame f. Theupper arm of the lever o is slotted to receive a bolt g, which holds ablock b in place on the lever. This block. carries an antifrictionalroller i, which engages the outer wall of the keeper 1). The block h isadjustable for the purpose of changing the bearing-point on the keeper,and thereby regulating'the length of the tables stroke. The lower arm ofthe lever c is provided with a bearing 1', which is engaged by oneextremity of a link It. This link is connected at Z with a link in,forming a toggle-joint. One extremity of the link engages a bar j,attached to the stationary frame. The pin connecting the two toggleparts also passes through one extremity of a pitman m, whose oppositeextremity is connected with a wrist n on a crank 0, carried by a shaft1), journaled in an upright support 7', mounted on the stationary framef. The shaft 1) is provided with tight and loose pulleys s, which may beconnected with any suitable motor for operating the mechanism. The outerextremities of the toggle are open, being simply recessed or forked toengage the bearings j and respectively. Hence as the shaft 1) is rotatedthe toggles only impart the backward movement to the table or move ittoward the left. The forward or reverse movement is effected or impartedby the recoil of a spring t, which is compressed or placed under tensionby the table during its backward movement.

In the operation of the machine the material to be treated is dischargedin the form of pulp upon the upper right-hand corner of the tablethrough the supply-trough H. (See Fig. 1.) The gangue or waste passestransversely downward over the longitudinal riflies and is dischargedover the apron G at the lower edge of the table, the middlings, or thatportion partially separated or which still contains a percentage of themore precious minerals, is carried through the space D at the end of thetable into the trough or spout E and back by way of the elevator F andspout M onto the table to be treated again and more thoroughlyseparated, while the mineral is discharged over the foot into thereceptacle 0. All the mineral, together with a portion of the gangue, isfirst caught by the riffies and under the influence of the tables motionis carried longitudinally toward the foot until it reaches the smootherunriffled portion B, where it is acted on by the water, which effects aperfect or approximatelyperfect separation of the gangue from themineral. As the material caught by the uppermost and shortest rifiiepasses to the portion B of the table the action of the water, which isfed to the upper edge of the table, carries the gangue downward to thenext riflie, while the mineral remains on the smooth portion B and iscarried toward the tail of the table, where it is finally discharged. Itis expected that some of the mineral caught by the uppermost andshortest riiile will be carried downward with the gangue to the nextrifiie, which is longer: Afterleavingthislastnamed riffle and passing tothe smooth or unriffled portion of the table the water again acts on thematerial and carries the gangue downward to the next rifiie, leaving theclean mineral on the smooth portion B of the table.

In this manner the material is carried transversely downward andlongitudinally forward, the gangue being discharged at the lower edge ofthe table completely impoverished of its mineral values, and thepartially-separated material or middlings are discharged through theaperture D into the trough 1C and returned to undergo anotherseparation, while the richest portion is discharged at the foot or tailof the table. A portion of the gangue that is to say, the light partthereof passes over each riffle in succession from the shortest oruppermost to the longest or lowermost riffie. The mineral and theheavier gangue are caught by the rifiies and finally separated on thesmooth portion B of the table.

The essential feature of this invention is my improved method of actingupon and saying the middlings. The middlings are of a comparativelylight weight, and when they are first deposited upon the table with therest of the gangue they are not able to free themselves and entirelywithstand the strong flow of the mass with which they are mixed in theirfirst passage across the table and are therefore carried through theaperture 1) and dcposited in the middlings-trough at the lower left-handcorner, whence they are returned and again deposited on the table, thistime beyond this strong flow of material, where the water alone can actupon the particles and finally wash and free them from the gangue,allowing them to be carried and deposited in the receptacle C at thefoot of the table and saved. The idea of carrying and depositing thesereturned middlings around and beyond the point where the pulp isprimarily fed to the machine is of great inn'iortance and has been sodemonstrated in practice. For example, should the middlings be depositedon the table at-any point above the pulp-feed instead of below it theselight particles would again be swept away by the flow of the gangue, asthey were the first time, and could not be saved, as is now the case, bythe use of my improved method. These middlings constitute a veryconsiderable proportion of the whole values in the pulp, and byreturning them to the table in the manner above described a much largerpercentage of the valuable mineral is saved.

Having thus described my invention, what 'I claim as new, and desire tosoon re by Letters Patent, is

1. A device of the character described, eomprising aconcentrating-table, a distributingtrough arranged. near one sidethereof and having perforations in its outer side, said trough beingelevated, whereby middlings may pass thereunder, a second troughelevated above the plane of said discharge-trough and terminating at apoint beyond the outer sideof the latter and nearer the concentratedischarge than the initial pulp-feed, means for collecting the middlingsfrom said table and delivering them to said elevated trough, andmeansfor supplying Water to said distributing-trough.

2. A device of the character described, comprising aconcentrating-table, a distributingtrough arranged near one side thereofand having perforations in its outer side, said trough being elevated, apulp-feeding pocket formed in said trough, an inclined trough located atthe opposite side of said table and leading from,

the lower end thereof, an apron'located over GEORGE E. PERKINS.

In presence of .H WARD E. BARLOW,

E; LOGDEN. v

